EP-A-0125788 discloses continuous extrusion apparatus having a rotatable wheel formed with two identical circumferential grooves, arcuate tooling bounding radially outer portions of the respective grooves, a die body provided with exit apertures extending in a generally radial direction from the respective grooves to an extrusion chamber positioned around a portal mandrel and discharging axially of the mandrel through a die orifice of uninterrupted annular cross-section intermediate the mandrel and a die body wall and a device is provided arranged to supply a core through the mandrel.